This invention relates to automotive alternator rectifier bridges and the fabrication thereof.
The three-phase alternators now almost universally used in vehicular applications for generation of electrical power rely on a rectifier bridge circuit to provide relatively high current, low voltage direct current to the increasingly heavy electrical loads that must be supplied. These rectifier bridges generally employ three negative and three positive diode rectifiers mounted on respective brackets or bases as part of the alternator assembly. They must operate reliably for long periods of time in the hostile environment of the engine compartment of the vehicle where they must withstand wide extremes of temperature. Typically six silicon rectifier chips, each sealed and mounted in a metal can, have been mechanically secured or soldered to metal base members which serve as heat sinks for the dissipation of heat generated by the diodes during operation. These bases or brackets have been formed from solid copper or aluminum and nickel-plated steel and frequently include a heavy solid set of cast heat-radiating fins to maintain the operating temperature of the bridge within acceptable limits. These bridges have been relatively complex in structure, required rather extensive and costly fabrication procedures, and were, as a result, rather expensive.